diff --git a/Firmware/util.h b/Firmware/util.h
index dca66b2fe..86d99827b 100644
--- a/Firmware/util.h
+++ b/Firmware/util.h
@@ -96,7 +96,7 @@ public:
     : len(0)
     , found(false)
     {
-        char * pStrEnd = NULL;
+        const char * pStrEnd = NULL;
 
         // Start of the string
         this->ptr = strchr(pStr, '"');